冠心病患者QT离散度与冬眠心肌关系的初步探讨

Primary investigation of the relationship between QT dispersion and hibernating myocardium in patients with coronary artery disease

目的 探讨冠心病患者 QT离散度 (QTd)与冬眠心肌的量化关系。方法 5 3例存在节段心肌收缩功能不全的冠心病患者行超声心动图、心电图和核素心肌显像 ,经皮腔内冠状动脉成形术 (PTCA)术后 1周复查超声心动图和心电图。结果 1全组 QTd从术前的 65 .85± 2 5 .83 ms降至术后的 5 6.79± 2 9.73 m s(P<0 .0 0 1)。2有节段收缩功能改善的病人 (IP组 ) QTd显著小于无节段功能改善的病人 (NIP组 ) (P<0 .0 0 1) ;术前 QTd与术后左心室整体室壁运动指数 (WMSI)的变化呈中度负相关 (r=- 0 .48,P<0 .0 0 1)。 3术后 IP组 QTd显著降低 (P<0 .0 0 1) ,而NIP组无显著变化 ;术后 QTd降低的幅度与 WMSI的降低程度呈中度正相关 (r=0 .63 ,P<0 .0 0 1)。4冬眠心肌检测阳性组 QTd显著小于检测阴性组 (P<0 .0 0 1)。结论 QT离散度与冠心病患者的冬眠心肌数量有关 。

Objective To investigate the relationship between QT dispersion (QTd) and hibernating myocardium in patients with coronary artery disease. Methods 53 patients with coronary artery disease and segmental dysfunction underwent echocardiography, electrocardiography and radionuclide imaging. Echocardiography and electrocardiography were repeated at 1 week after precutaneous transluminal coronary angioplasty(PTCA).Results ①The average QTd decreased from 65.85±25.83 ms at baseline to 56.79±29.73 ms after PTCA ( P <0.001). ②The patients with functional improvement (group IP) had significantly shorter QTd than those without functional improvement (group NIP) ( P <0.001). The QTd at baseline was negatively related to the change of global wall motion score index (WMSI) of the left ventricle after PTCA ( r =-0.48, P <0.001). ③The QTd in group IP was significantly decreased after PTCA ( P <0.001) and that in group NIP was not. The shortening extent of QTd after PTCA was positively related to the lowering extent of WMSI ( r =0.63, P <0.001). Conclusion QTd dispersion is related to the extent of hibernating myocardium in patients with coronary artery disease.